Conventionally, the system disclosed in Patent Document 1 is known as such a system. The center of the system prescribes transmission condition to a vehicle in advance. When the transmission condition is met in the vehicle, vehicle data is transmitted to the center from the vehicle. Specifically, when the transmission condition is met in the vehicle, the data transmission buffer of the vehicle stores vehicle data prescribed as a data item to be acquired. Then, the vehicle data stored in the data transmission buffer is transmitted to the center from the vehicle either periodically or in response to a request from the center.